2 * Copyright (c) 2015 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
16 * buffer_funcs.h: VLIB buffer related functions/inlines
18 * Copyright (c) 2008 Eliot Dresselhaus
20 * Permission is hereby granted, free of charge, to any person obtaining
21 * a copy of this software and associated documentation files (the
22 * "Software"), to deal in the Software without restriction, including
23 * without limitation the rights to use, copy, modify, merge, publish,
24 * distribute, sublicense, and/or sell copies of the Software, and to
25 * permit persons to whom the Software is furnished to do so, subject to
26 * the following conditions:
28 * The above copyright notice and this permission notice shall be
29 * included in all copies or substantial portions of the Software.
31 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
32 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
33 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
34 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
35 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
36 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
37 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
40 #ifndef included_vlib_buffer_funcs_h
41 #define included_vlib_buffer_funcs_h
43 #include <vppinfra/hash.h>
44 #include <vppinfra/fifo.h>
47 vlib buffer access methods.
51 /** \brief Translate buffer index into buffer pointer
53 @param vm - (vlib_main_t *) vlib main data structure pointer
54 @param buffer_index - (u32) buffer index
55 @return - (vlib_buffer_t *) buffer pointer
57 always_inline vlib_buffer_t *
58 vlib_get_buffer (vlib_main_t * vm, u32 buffer_index)
60 vlib_buffer_main_t *bm = vm->buffer_main;
61 uword offset = ((uword) buffer_index) << CLIB_LOG2_CACHE_LINE_BYTES;
62 ASSERT (offset < bm->buffer_mem_size);
64 return uword_to_pointer (bm->buffer_mem_start + offset, void *);
67 static_always_inline void
68 vlib_buffer_copy_indices (u32 * dst, u32 * src, u32 n_indices)
70 clib_memcpy_fast (dst, src, n_indices * sizeof (u32));
73 STATIC_ASSERT_OFFSET_OF (vlib_buffer_t, template_end, 64);
74 static_always_inline void
75 vlib_buffer_copy_template (vlib_buffer_t * b, vlib_buffer_t * bt)
77 #if defined CLIB_HAVE_VEC512
78 b->as_u8x64[0] = bt->as_u8x64[0];
79 #elif defined (CLIB_HAVE_VEC256)
80 b->as_u8x32[0] = bt->as_u8x32[0];
81 b->as_u8x32[1] = bt->as_u8x32[1];
82 #elif defined (CLIB_HAVE_VEC128)
83 b->as_u8x16[0] = bt->as_u8x16[0];
84 b->as_u8x16[1] = bt->as_u8x16[1];
85 b->as_u8x16[2] = bt->as_u8x16[2];
86 b->as_u8x16[3] = bt->as_u8x16[3];
88 clib_memcpy_fast (b, bt, 64);
92 /** \brief Translate array of buffer indices into buffer pointers with offset
94 @param vm - (vlib_main_t *) vlib main data structure pointer
95 @param bi - (u32 *) array of buffer indices
96 @param b - (void **) array to store buffer pointers
97 @param count - (uword) number of elements
98 @param offset - (i32) offset applied to each pointer
100 static_always_inline void
101 vlib_get_buffers_with_offset (vlib_main_t * vm, u32 * bi, void **b, int count,
104 #if defined (CLIB_HAVE_VEC256) || defined (CLIB_HAVE_VEC128)
105 uword buffer_mem_start = vm->buffer_main->buffer_mem_start;
107 #ifdef CLIB_HAVE_VEC256
108 u64x4 off = u64x4_splat (buffer_mem_start + offset);
109 /* if count is not const, compiler will not unroll while loop
110 se we maintain two-in-parallel variant */
113 u64x4 b0 = u32x4_extend_to_u64x4 (u32x4_load_unaligned (bi));
114 u64x4 b1 = u32x4_extend_to_u64x4 (u32x4_load_unaligned (bi + 4));
115 /* shift and add to get vlib_buffer_t pointer */
116 u64x4_store_unaligned ((b0 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b);
117 u64x4_store_unaligned ((b1 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b + 4);
125 #ifdef CLIB_HAVE_VEC256
126 u64x4 b0 = u32x4_extend_to_u64x4 (u32x4_load_unaligned (bi));
127 /* shift and add to get vlib_buffer_t pointer */
128 u64x4_store_unaligned ((b0 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b);
129 #elif defined (CLIB_HAVE_VEC128)
130 u64x2 off = u64x2_splat (buffer_mem_start + offset);
131 u32x4 bi4 = u32x4_load_unaligned (bi);
132 u64x2 b0 = u32x4_extend_to_u64x2 ((u32x4) bi4);
133 #if defined (__aarch64__)
134 u64x2 b1 = u32x4_extend_to_u64x2_high ((u32x4) bi4);
136 bi4 = u32x4_shuffle (bi4, 2, 3, 0, 1);
137 u64x2 b1 = u32x4_extend_to_u64x2 ((u32x4) bi4);
139 u64x2_store_unaligned ((b0 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b);
140 u64x2_store_unaligned ((b1 << CLIB_LOG2_CACHE_LINE_BYTES) + off, b + 2);
142 b[0] = ((u8 *) vlib_get_buffer (vm, bi[0])) + offset;
143 b[1] = ((u8 *) vlib_get_buffer (vm, bi[1])) + offset;
144 b[2] = ((u8 *) vlib_get_buffer (vm, bi[2])) + offset;
145 b[3] = ((u8 *) vlib_get_buffer (vm, bi[3])) + offset;
153 b[0] = ((u8 *) vlib_get_buffer (vm, bi[0])) + offset;
160 /** \brief Translate array of buffer indices into buffer pointers
162 @param vm - (vlib_main_t *) vlib main data structure pointer
163 @param bi - (u32 *) array of buffer indices
164 @param b - (vlib_buffer_t **) array to store buffer pointers
165 @param count - (uword) number of elements
168 static_always_inline void
169 vlib_get_buffers (vlib_main_t * vm, u32 * bi, vlib_buffer_t ** b, int count)
171 vlib_get_buffers_with_offset (vm, bi, (void **) b, count, 0);
174 /** \brief Translate buffer pointer into buffer index
176 @param vm - (vlib_main_t *) vlib main data structure pointer
177 @param p - (void *) buffer pointer
178 @return - (u32) buffer index
182 vlib_get_buffer_index (vlib_main_t * vm, void *p)
184 vlib_buffer_main_t *bm = vm->buffer_main;
185 uword offset = pointer_to_uword (p) - bm->buffer_mem_start;
186 ASSERT (pointer_to_uword (p) >= bm->buffer_mem_start);
187 ASSERT (offset < bm->buffer_mem_size);
188 ASSERT ((offset % (1 << CLIB_LOG2_CACHE_LINE_BYTES)) == 0);
189 return offset >> CLIB_LOG2_CACHE_LINE_BYTES;
192 /** \brief Translate array of buffer pointers into buffer indices with offset
194 @param vm - (vlib_main_t *) vlib main data structure pointer
195 @param b - (void **) array of buffer pointers
196 @param bi - (u32 *) array to store buffer indices
197 @param count - (uword) number of elements
198 @param offset - (i32) offset applied to each pointer
200 static_always_inline void
201 vlib_get_buffer_indices_with_offset (vlib_main_t * vm, void **b, u32 * bi,
202 uword count, i32 offset)
204 #ifdef CLIB_HAVE_VEC256
205 u32x8 mask = { 0, 2, 4, 6, 1, 3, 5, 7 };
206 u64x4 off4 = u64x4_splat (vm->buffer_main->buffer_mem_start - offset);
210 /* load 4 pointers into 256-bit register */
211 u64x4 v0 = u64x4_load_unaligned (b);
212 u64x4 v1 = u64x4_load_unaligned (b + 4);
218 v0 >>= CLIB_LOG2_CACHE_LINE_BYTES;
219 v1 >>= CLIB_LOG2_CACHE_LINE_BYTES;
221 /* permute 256-bit register so lower u32s of each buffer index are
222 * placed into lower 128-bits */
223 v2 = u32x8_permute ((u32x8) v0, mask);
224 v3 = u32x8_permute ((u32x8) v1, mask);
226 /* extract lower 128-bits and save them to the array of buffer indices */
227 u32x4_store_unaligned (u32x8_extract_lo (v2), bi);
228 u32x4_store_unaligned (u32x8_extract_lo (v3), bi + 4);
236 /* equivalent non-nector implementation */
237 bi[0] = vlib_get_buffer_index (vm, ((u8 *) b[0]) + offset);
238 bi[1] = vlib_get_buffer_index (vm, ((u8 *) b[1]) + offset);
239 bi[2] = vlib_get_buffer_index (vm, ((u8 *) b[2]) + offset);
240 bi[3] = vlib_get_buffer_index (vm, ((u8 *) b[3]) + offset);
247 bi[0] = vlib_get_buffer_index (vm, ((u8 *) b[0]) + offset);
254 /** \brief Translate array of buffer pointers into buffer indices
256 @param vm - (vlib_main_t *) vlib main data structure pointer
257 @param b - (vlib_buffer_t **) array of buffer pointers
258 @param bi - (u32 *) array to store buffer indices
259 @param count - (uword) number of elements
261 static_always_inline void
262 vlib_get_buffer_indices (vlib_main_t * vm, vlib_buffer_t ** b, u32 * bi,
265 vlib_get_buffer_indices_with_offset (vm, (void **) b, bi, count, 0);
268 /** \brief Get next buffer in buffer linklist, or zero for end of list.
270 @param vm - (vlib_main_t *) vlib main data structure pointer
271 @param b - (void *) buffer pointer
272 @return - (vlib_buffer_t *) next buffer, or NULL
274 always_inline vlib_buffer_t *
275 vlib_get_next_buffer (vlib_main_t * vm, vlib_buffer_t * b)
277 return (b->flags & VLIB_BUFFER_NEXT_PRESENT
278 ? vlib_get_buffer (vm, b->next_buffer) : 0);
281 uword vlib_buffer_length_in_chain_slow_path (vlib_main_t * vm,
282 vlib_buffer_t * b_first);
284 /** \brief Get length in bytes of the buffer chain
286 @param vm - (vlib_main_t *) vlib main data structure pointer
287 @param b - (void *) buffer pointer
288 @return - (uword) length of buffer chain
291 vlib_buffer_length_in_chain (vlib_main_t * vm, vlib_buffer_t * b)
293 uword len = b->current_length;
295 if (PREDICT_TRUE ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0))
298 if (PREDICT_TRUE (b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID))
299 return len + b->total_length_not_including_first_buffer;
301 return vlib_buffer_length_in_chain_slow_path (vm, b);
304 /** \brief Get length in bytes of the buffer index buffer chain
306 @param vm - (vlib_main_t *) vlib main data structure pointer
307 @param bi - (u32) buffer index
308 @return - (uword) length of buffer chain
311 vlib_buffer_index_length_in_chain (vlib_main_t * vm, u32 bi)
313 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
314 return vlib_buffer_length_in_chain (vm, b);
317 /** \brief Copy buffer contents to memory
319 @param vm - (vlib_main_t *) vlib main data structure pointer
320 @param buffer_index - (u32) buffer index
321 @param contents - (u8 *) memory, <strong>must be large enough</strong>
322 @return - (uword) length of buffer chain
325 vlib_buffer_contents (vlib_main_t * vm, u32 buffer_index, u8 * contents)
327 uword content_len = 0;
333 b = vlib_get_buffer (vm, buffer_index);
334 l = b->current_length;
335 clib_memcpy_fast (contents + content_len, b->data + b->current_data, l);
337 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
339 buffer_index = b->next_buffer;
346 vlib_buffer_get_pa (vlib_main_t * vm, vlib_buffer_t * b)
348 return vlib_physmem_get_pa (vm, b->data);
352 vlib_buffer_get_current_pa (vlib_main_t * vm, vlib_buffer_t * b)
354 return vlib_buffer_get_pa (vm, b) + b->current_data;
357 /** \brief Prefetch buffer metadata by buffer index
358 The first 64 bytes of buffer contains most header information
360 @param vm - (vlib_main_t *) vlib main data structure pointer
361 @param bi - (u32) buffer index
362 @param type - LOAD, STORE. In most cases, STORE is the right answer
364 /* Prefetch buffer header given index. */
365 #define vlib_prefetch_buffer_with_index(vm,bi,type) \
367 vlib_buffer_t * _b = vlib_get_buffer (vm, bi); \
368 vlib_prefetch_buffer_header (_b, type); \
373 /* Index is unknown. */
376 /* Index is known and free/allocated. */
377 VLIB_BUFFER_KNOWN_FREE,
378 VLIB_BUFFER_KNOWN_ALLOCATED,
379 } vlib_buffer_known_state_t;
381 void vlib_buffer_validate_alloc_free (vlib_main_t * vm, u32 * buffers,
383 vlib_buffer_known_state_t
386 always_inline vlib_buffer_known_state_t
387 vlib_buffer_is_known (vlib_main_t * vm, u32 buffer_index)
389 vlib_buffer_main_t *bm = vm->buffer_main;
391 clib_spinlock_lock (&bm->buffer_known_hash_lockp);
392 uword *p = hash_get (bm->buffer_known_hash, buffer_index);
393 clib_spinlock_unlock (&bm->buffer_known_hash_lockp);
394 return p ? p[0] : VLIB_BUFFER_UNKNOWN;
398 vlib_buffer_set_known_state (vlib_main_t * vm, u32 buffer_index,
399 vlib_buffer_known_state_t state)
401 vlib_buffer_main_t *bm = vm->buffer_main;
403 clib_spinlock_lock (&bm->buffer_known_hash_lockp);
404 hash_set (bm->buffer_known_hash, buffer_index, state);
405 clib_spinlock_unlock (&bm->buffer_known_hash_lockp);
408 /* Validates sanity of a single buffer.
409 Returns format'ed vector with error message if any. */
410 u8 *vlib_validate_buffer (vlib_main_t * vm, u32 buffer_index,
414 vlib_buffer_round_size (u32 size)
416 return round_pow2 (size, sizeof (vlib_buffer_t));
419 /** \brief Allocate buffers from specific freelist into supplied array
421 @param vm - (vlib_main_t *) vlib main data structure pointer
422 @param buffers - (u32 * ) buffer index array
423 @param n_buffers - (u32) number of buffers requested
424 @return - (u32) number of buffers actually allocated, may be
425 less than the number requested or zero
428 vlib_buffer_alloc_from_free_list (vlib_main_t * vm,
431 vlib_buffer_free_list_index_t index)
433 vlib_buffer_free_list_t *fl;
434 vlib_buffer_main_t *bm = vm->buffer_main;
438 ASSERT (bm->cb.vlib_buffer_fill_free_list_cb);
440 fl = pool_elt_at_index (vm->buffer_free_list_pool, index);
442 len = vec_len (fl->buffers);
444 if (PREDICT_FALSE (len < n_buffers))
446 bm->cb.vlib_buffer_fill_free_list_cb (vm, fl, n_buffers);
447 if (PREDICT_FALSE ((len = vec_len (fl->buffers)) == 0))
450 /* even if fill free list didn't manage to refill free list
451 we should give what we have */
452 n_buffers = clib_min (len, n_buffers);
454 /* following code is intentionaly duplicated to allow compiler
455 to optimize fast path when n_buffers is constant value */
456 src = fl->buffers + len - n_buffers;
457 vlib_buffer_copy_indices (buffers, src, n_buffers);
458 _vec_len (fl->buffers) -= n_buffers;
460 /* Verify that buffers are known free. */
461 vlib_buffer_validate_alloc_free (vm, buffers, n_buffers,
462 VLIB_BUFFER_KNOWN_FREE);
467 src = fl->buffers + len - n_buffers;
468 vlib_buffer_copy_indices (buffers, src, n_buffers);
469 _vec_len (fl->buffers) -= n_buffers;
471 /* Verify that buffers are known free. */
472 vlib_buffer_validate_alloc_free (vm, buffers, n_buffers,
473 VLIB_BUFFER_KNOWN_FREE);
478 /** \brief Allocate buffers into supplied array
480 @param vm - (vlib_main_t *) vlib main data structure pointer
481 @param buffers - (u32 * ) buffer index array
482 @param n_buffers - (u32) number of buffers requested
483 @return - (u32) number of buffers actually allocated, may be
484 less than the number requested or zero
487 vlib_buffer_alloc (vlib_main_t * vm, u32 * buffers, u32 n_buffers)
489 return vlib_buffer_alloc_from_free_list (vm, buffers, n_buffers,
490 VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX);
493 /** \brief Allocate buffers into ring
495 @param vm - (vlib_main_t *) vlib main data structure pointer
496 @param buffers - (u32 * ) buffer index ring
497 @param start - (u32) first slot in the ring
498 @param ring_size - (u32) ring size
499 @param n_buffers - (u32) number of buffers requested
500 @return - (u32) number of buffers actually allocated, may be
501 less than the number requested or zero
504 vlib_buffer_alloc_to_ring (vlib_main_t * vm, u32 * ring, u32 start,
505 u32 ring_size, u32 n_buffers)
509 ASSERT (n_buffers <= ring_size);
511 if (PREDICT_TRUE (start + n_buffers <= ring_size))
512 return vlib_buffer_alloc (vm, ring + start, n_buffers);
514 n_alloc = vlib_buffer_alloc (vm, ring + start, ring_size - start);
516 if (PREDICT_TRUE (n_alloc == ring_size - start))
517 n_alloc += vlib_buffer_alloc (vm, ring, n_buffers - n_alloc);
522 /** \brief Free buffers
523 Frees the entire buffer chain for each buffer
525 @param vm - (vlib_main_t *) vlib main data structure pointer
526 @param buffers - (u32 * ) buffer index array
527 @param n_buffers - (u32) number of buffers to free
531 vlib_buffer_free (vlib_main_t * vm,
532 /* pointer to first buffer */
534 /* number of buffers to free */
537 vlib_buffer_main_t *bm = vm->buffer_main;
539 ASSERT (bm->cb.vlib_buffer_free_cb);
541 return bm->cb.vlib_buffer_free_cb (vm, buffers, n_buffers);
544 /** \brief Free buffers, does not free the buffer chain for each buffer
546 @param vm - (vlib_main_t *) vlib main data structure pointer
547 @param buffers - (u32 * ) buffer index array
548 @param n_buffers - (u32) number of buffers to free
552 vlib_buffer_free_no_next (vlib_main_t * vm,
553 /* pointer to first buffer */
555 /* number of buffers to free */
558 vlib_buffer_main_t *bm = vm->buffer_main;
560 ASSERT (bm->cb.vlib_buffer_free_no_next_cb);
562 return bm->cb.vlib_buffer_free_no_next_cb (vm, buffers, n_buffers);
565 /** \brief Free one buffer
566 Shorthand to free a single buffer chain.
568 @param vm - (vlib_main_t *) vlib main data structure pointer
569 @param buffer_index - (u32) buffer index to free
572 vlib_buffer_free_one (vlib_main_t * vm, u32 buffer_index)
574 vlib_buffer_free (vm, &buffer_index, /* n_buffers */ 1);
577 /** \brief Free buffers from ring
579 @param vm - (vlib_main_t *) vlib main data structure pointer
580 @param buffers - (u32 * ) buffer index ring
581 @param start - (u32) first slot in the ring
582 @param ring_size - (u32) ring size
583 @param n_buffers - (u32) number of buffers
586 vlib_buffer_free_from_ring (vlib_main_t * vm, u32 * ring, u32 start,
587 u32 ring_size, u32 n_buffers)
589 ASSERT (n_buffers <= ring_size);
591 if (PREDICT_TRUE (start + n_buffers <= ring_size))
593 vlib_buffer_free (vm, ring + start, n_buffers);
597 vlib_buffer_free (vm, ring + start, ring_size - start);
598 vlib_buffer_free (vm, ring, n_buffers - (ring_size - start));
602 /** \brief Free buffers from ring without freeing tail buffers
604 @param vm - (vlib_main_t *) vlib main data structure pointer
605 @param buffers - (u32 * ) buffer index ring
606 @param start - (u32) first slot in the ring
607 @param ring_size - (u32) ring size
608 @param n_buffers - (u32) number of buffers
611 vlib_buffer_free_from_ring_no_next (vlib_main_t * vm, u32 * ring, u32 start,
612 u32 ring_size, u32 n_buffers)
614 ASSERT (n_buffers <= ring_size);
616 if (PREDICT_TRUE (start + n_buffers <= ring_size))
618 vlib_buffer_free_no_next (vm, ring + start, n_buffers);
622 vlib_buffer_free_no_next (vm, ring + start, ring_size - start);
623 vlib_buffer_free_no_next (vm, ring, n_buffers - (ring_size - start));
627 /* Add/delete buffer free lists. */
628 vlib_buffer_free_list_index_t vlib_buffer_create_free_list (vlib_main_t * vm,
632 /* Append given data to end of buffer, possibly allocating new buffers. */
633 int vlib_buffer_add_data (vlib_main_t * vm, u32 * buffer_index, void *data,
636 /* duplicate all buffers in chain */
637 always_inline vlib_buffer_t *
638 vlib_buffer_copy (vlib_main_t * vm, vlib_buffer_t * b)
640 vlib_buffer_t *s, *d, *fd;
641 uword n_alloc, n_buffers = 1;
642 u32 flag_mask = VLIB_BUFFER_NEXT_PRESENT | VLIB_BUFFER_TOTAL_LENGTH_VALID;
646 while (s->flags & VLIB_BUFFER_NEXT_PRESENT)
649 s = vlib_get_buffer (vm, s->next_buffer);
651 u32 new_buffers[n_buffers];
653 n_alloc = vlib_buffer_alloc (vm, new_buffers, n_buffers);
655 /* No guarantee that we'll get all the buffers we asked for */
656 if (PREDICT_FALSE (n_alloc < n_buffers))
659 vlib_buffer_free (vm, new_buffers, n_alloc);
665 fd = d = vlib_get_buffer (vm, new_buffers[0]);
666 d->current_data = s->current_data;
667 d->current_length = s->current_length;
668 d->flags = s->flags & flag_mask;
669 d->total_length_not_including_first_buffer =
670 s->total_length_not_including_first_buffer;
671 clib_memcpy_fast (d->opaque, s->opaque, sizeof (s->opaque));
672 clib_memcpy_fast (d->opaque2, s->opaque2, sizeof (s->opaque2));
673 clib_memcpy_fast (vlib_buffer_get_current (d),
674 vlib_buffer_get_current (s), s->current_length);
677 for (i = 1; i < n_buffers; i++)
680 d->next_buffer = new_buffers[i];
682 s = vlib_get_buffer (vm, s->next_buffer);
683 d = vlib_get_buffer (vm, new_buffers[i]);
684 d->current_data = s->current_data;
685 d->current_length = s->current_length;
686 clib_memcpy_fast (vlib_buffer_get_current (d),
687 vlib_buffer_get_current (s), s->current_length);
688 d->flags = s->flags & flag_mask;
694 /** \brief Create a maximum of 256 clones of buffer and store them
695 in the supplied array
697 @param vm - (vlib_main_t *) vlib main data structure pointer
698 @param src_buffer - (u32) source buffer index
699 @param buffers - (u32 * ) buffer index array
700 @param n_buffers - (u16) number of buffer clones requested (<=256)
701 @param head_end_offset - (u16) offset relative to current position
702 where packet head ends
703 @return - (u16) number of buffers actually cloned, may be
704 less than the number requested or zero
707 vlib_buffer_clone_256 (vlib_main_t * vm, u32 src_buffer, u32 * buffers,
708 u16 n_buffers, u16 head_end_offset)
711 vlib_buffer_t *s = vlib_get_buffer (vm, src_buffer);
713 ASSERT (s->n_add_refs == 0);
715 ASSERT (n_buffers <= 256);
717 if (s->current_length <= head_end_offset + CLIB_CACHE_LINE_BYTES * 2)
719 buffers[0] = src_buffer;
720 for (i = 1; i < n_buffers; i++)
723 d = vlib_buffer_copy (vm, s);
726 buffers[i] = vlib_get_buffer_index (vm, d);
732 if (PREDICT_FALSE (n_buffers == 1))
734 buffers[0] = src_buffer;
738 n_buffers = vlib_buffer_alloc (vm, buffers, n_buffers);
740 for (i = 0; i < n_buffers; i++)
742 vlib_buffer_t *d = vlib_get_buffer (vm, buffers[i]);
743 d->current_data = s->current_data;
744 d->current_length = head_end_offset;
745 d->total_length_not_including_first_buffer = s->current_length -
747 if (PREDICT_FALSE (s->flags & VLIB_BUFFER_NEXT_PRESENT))
749 d->total_length_not_including_first_buffer +=
750 s->total_length_not_including_first_buffer;
752 d->flags = s->flags | VLIB_BUFFER_NEXT_PRESENT;
753 d->flags &= ~VLIB_BUFFER_EXT_HDR_VALID;
754 clib_memcpy_fast (d->opaque, s->opaque, sizeof (s->opaque));
755 clib_memcpy_fast (d->opaque2, s->opaque2, sizeof (s->opaque2));
756 clib_memcpy_fast (vlib_buffer_get_current (d),
757 vlib_buffer_get_current (s), head_end_offset);
758 d->next_buffer = src_buffer;
760 vlib_buffer_advance (s, head_end_offset);
761 s->n_add_refs = n_buffers - 1;
762 while (s->flags & VLIB_BUFFER_NEXT_PRESENT)
764 s = vlib_get_buffer (vm, s->next_buffer);
765 s->n_add_refs = n_buffers - 1;
771 /** \brief Create multiple clones of buffer and store them
772 in the supplied array
774 @param vm - (vlib_main_t *) vlib main data structure pointer
775 @param src_buffer - (u32) source buffer index
776 @param buffers - (u32 * ) buffer index array
777 @param n_buffers - (u16) number of buffer clones requested (<=256)
778 @param head_end_offset - (u16) offset relative to current position
779 where packet head ends
780 @return - (u16) number of buffers actually cloned, may be
781 less than the number requested or zero
784 vlib_buffer_clone (vlib_main_t * vm, u32 src_buffer, u32 * buffers,
785 u16 n_buffers, u16 head_end_offset)
787 vlib_buffer_t *s = vlib_get_buffer (vm, src_buffer);
790 while (n_buffers > 256)
793 copy = vlib_buffer_copy (vm, s);
794 n_cloned += vlib_buffer_clone_256 (vm,
795 vlib_get_buffer_index (vm, copy),
796 (buffers + n_cloned),
797 256, head_end_offset);
800 n_cloned += vlib_buffer_clone_256 (vm, src_buffer,
802 n_buffers, head_end_offset);
807 /** \brief Attach cloned tail to the buffer
809 @param vm - (vlib_main_t *) vlib main data structure pointer
810 @param head - (vlib_buffer_t *) head buffer
811 @param tail - (Vlib buffer_t *) tail buffer to clone and attach to head
815 vlib_buffer_attach_clone (vlib_main_t * vm, vlib_buffer_t * head,
816 vlib_buffer_t * tail)
818 ASSERT ((head->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
820 head->flags |= VLIB_BUFFER_NEXT_PRESENT;
821 head->flags &= ~VLIB_BUFFER_TOTAL_LENGTH_VALID;
822 head->flags &= ~VLIB_BUFFER_EXT_HDR_VALID;
823 head->flags |= (tail->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID);
824 head->next_buffer = vlib_get_buffer_index (vm, tail);
825 head->total_length_not_including_first_buffer = tail->current_length +
826 tail->total_length_not_including_first_buffer;
829 clib_atomic_add_fetch (&tail->n_add_refs, 1);
831 if (tail->flags & VLIB_BUFFER_NEXT_PRESENT)
833 tail = vlib_get_buffer (vm, tail->next_buffer);
838 /* Initializes the buffer as an empty packet with no chained buffers. */
840 vlib_buffer_chain_init (vlib_buffer_t * first)
842 first->total_length_not_including_first_buffer = 0;
843 first->current_length = 0;
844 first->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
845 first->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
848 /* The provided next_bi buffer index is appended to the end of the packet. */
849 always_inline vlib_buffer_t *
850 vlib_buffer_chain_buffer (vlib_main_t * vm, vlib_buffer_t * last, u32 next_bi)
852 vlib_buffer_t *next_buffer = vlib_get_buffer (vm, next_bi);
853 last->next_buffer = next_bi;
854 last->flags |= VLIB_BUFFER_NEXT_PRESENT;
855 next_buffer->current_length = 0;
856 next_buffer->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
860 /* Increases or decreases the packet length.
861 * It does not allocate or deallocate new buffers.
862 * Therefore, the added length must be compatible
863 * with the last buffer. */
865 vlib_buffer_chain_increase_length (vlib_buffer_t * first,
866 vlib_buffer_t * last, i32 len)
868 last->current_length += len;
870 first->total_length_not_including_first_buffer += len;
873 /* Copy data to the end of the packet and increases its length.
874 * It does not allocate new buffers.
875 * Returns the number of copied bytes. */
877 vlib_buffer_chain_append_data (vlib_main_t * vm,
878 vlib_buffer_free_list_index_t free_list_index,
879 vlib_buffer_t * first,
880 vlib_buffer_t * last, void *data, u16 data_len)
882 u32 n_buffer_bytes = VLIB_BUFFER_DATA_SIZE;
883 ASSERT (n_buffer_bytes >= last->current_length + last->current_data);
884 u16 len = clib_min (data_len,
885 n_buffer_bytes - last->current_length -
887 clib_memcpy_fast (vlib_buffer_get_current (last) + last->current_length,
889 vlib_buffer_chain_increase_length (first, last, len);
893 /* Copy data to the end of the packet and increases its length.
894 * Allocates additional buffers from the free list if necessary.
895 * Returns the number of copied bytes.
896 * 'last' value is modified whenever new buffers are allocated and
897 * chained and points to the last buffer in the chain. */
899 vlib_buffer_chain_append_data_with_alloc (vlib_main_t * vm,
900 vlib_buffer_free_list_index_t
902 vlib_buffer_t * first,
903 vlib_buffer_t ** last, void *data,
905 void vlib_buffer_chain_validate (vlib_main_t * vm, vlib_buffer_t * first);
907 format_function_t format_vlib_buffer, format_vlib_buffer_and_data,
908 format_vlib_buffer_contents;
912 /* Vector of packet data. */
915 /* Number of buffers to allocate in each call to allocator. */
916 u32 min_n_buffers_each_alloc;
918 /* Buffer free list for this template. */
919 vlib_buffer_free_list_index_t free_list_index;
924 } vlib_packet_template_t;
926 void vlib_packet_template_get_packet_helper (vlib_main_t * vm,
927 vlib_packet_template_t * t);
929 void vlib_packet_template_init (vlib_main_t * vm,
930 vlib_packet_template_t * t,
932 uword n_packet_data_bytes,
933 uword min_n_buffers_each_alloc,
936 void *vlib_packet_template_get_packet (vlib_main_t * vm,
937 vlib_packet_template_t * t,
941 vlib_packet_template_free (vlib_main_t * vm, vlib_packet_template_t * t)
943 vec_free (t->packet_data);
946 static_always_inline vlib_buffer_pool_t *
947 vlib_buffer_pool_get (vlib_main_t * vm, u8 buffer_pool_index)
949 vlib_buffer_main_t *bm = vm->buffer_main;
950 return vec_elt_at_index (bm->buffer_pools, buffer_pool_index);
954 vlib_buffer_add_to_free_list (vlib_main_t * vm,
955 vlib_buffer_free_list_t * f,
956 u32 buffer_index, u8 do_init)
958 vlib_buffer_pool_t *bp = vlib_buffer_pool_get (vm, f->buffer_pool_index);
960 b = vlib_get_buffer (vm, buffer_index);
961 if (PREDICT_TRUE (do_init))
962 clib_memset (b, 0, STRUCT_OFFSET_OF (vlib_buffer_t, template_end));
963 vec_add1_aligned (f->buffers, buffer_index, CLIB_CACHE_LINE_BYTES);
965 if (vec_len (f->buffers) > 4 * VLIB_FRAME_SIZE)
967 clib_spinlock_lock (&bp->lock);
968 /* keep last stored buffers, as they are more likely hot in the cache */
969 vec_add_aligned (bp->buffers, f->buffers, VLIB_FRAME_SIZE,
970 CLIB_CACHE_LINE_BYTES);
971 vec_delete (f->buffers, VLIB_FRAME_SIZE, 0);
972 f->n_alloc -= VLIB_FRAME_SIZE;
973 clib_spinlock_unlock (&bp->lock);
978 extern u32 *vlib_buffer_state_validation_lock;
979 extern uword *vlib_buffer_state_validation_hash;
980 extern void *vlib_buffer_state_heap;
984 vlib_validate_buffer_in_use (vlib_buffer_t * b, u32 expected)
990 oldheap = clib_mem_set_heap (vlib_buffer_state_heap);
992 while (clib_atomic_test_and_set (vlib_buffer_state_validation_lock))
995 p = hash_get (vlib_buffer_state_validation_hash, b);
997 /* If we don't know about b, declare it to be in the expected state */
1000 hash_set (vlib_buffer_state_validation_hash, b, expected);
1004 if (p[0] != expected)
1006 void cj_stop (void);
1008 vlib_main_t *vm = &vlib_global_main;
1012 bi = vlib_get_buffer_index (vm, b);
1014 clib_mem_set_heap (oldheap);
1015 clib_warning ("%.6f buffer %llx (%d): %s, not %s",
1016 vlib_time_now (vm), bi,
1017 p[0] ? "busy" : "free", expected ? "busy" : "free");
1021 CLIB_MEMORY_BARRIER ();
1022 *vlib_buffer_state_validation_lock = 0;
1023 clib_mem_set_heap (oldheap);
1028 vlib_validate_buffer_set_in_use (vlib_buffer_t * b, u32 expected)
1033 oldheap = clib_mem_set_heap (vlib_buffer_state_heap);
1035 while (clib_atomic_test_and_set (vlib_buffer_state_validation_lock))
1038 hash_set (vlib_buffer_state_validation_hash, b, expected);
1040 CLIB_MEMORY_BARRIER ();
1041 *vlib_buffer_state_validation_lock = 0;
1042 clib_mem_set_heap (oldheap);
1046 /** minimum data size of first buffer in a buffer chain */
1047 #define VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE (256)
1050 * @brief compress buffer chain in a way where the first buffer is at least
1051 * VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE long
1053 * @param[in] vm - vlib_main
1054 * @param[in,out] first - first buffer in chain
1055 * @param[in,out] discard_vector - vector of buffer indexes which were removed
1059 vlib_buffer_chain_compress (vlib_main_t * vm,
1060 vlib_buffer_t * first, u32 ** discard_vector)
1062 if (first->current_length >= VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE ||
1063 !(first->flags & VLIB_BUFFER_NEXT_PRESENT))
1065 /* this is already big enough or not a chain */
1069 u32 want_first_size = clib_min (VLIB_BUFFER_CHAIN_MIN_FIRST_DATA_SIZE,
1070 VLIB_BUFFER_DATA_SIZE -
1071 first->current_data);
1074 vlib_buffer_t *second = vlib_get_buffer (vm, first->next_buffer);
1075 u32 need = want_first_size - first->current_length;
1076 u32 amount_to_copy = clib_min (need, second->current_length);
1077 clib_memcpy_fast (((u8 *) vlib_buffer_get_current (first)) +
1078 first->current_length,
1079 vlib_buffer_get_current (second), amount_to_copy);
1080 first->current_length += amount_to_copy;
1081 second->current_data += amount_to_copy;
1082 second->current_length -= amount_to_copy;
1083 if (first->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID)
1085 first->total_length_not_including_first_buffer -= amount_to_copy;
1087 if (!second->current_length)
1089 vec_add1 (*discard_vector, first->next_buffer);
1090 if (second->flags & VLIB_BUFFER_NEXT_PRESENT)
1092 first->next_buffer = second->next_buffer;
1096 first->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
1098 second->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
1101 while ((first->current_length < want_first_size) &&
1102 (first->flags & VLIB_BUFFER_NEXT_PRESENT));
1106 * @brief linearize buffer chain - the first buffer is filled, if needed,
1107 * buffers are allocated and filled, returns free space in last buffer or
1108 * negative on failure
1110 * @param[in] vm - vlib_main
1111 * @param[in,out] first - first buffer in chain
1114 vlib_buffer_chain_linearize (vlib_main_t * vm, vlib_buffer_t * first)
1116 vlib_buffer_t *b = first;
1117 u32 buf_len = VLIB_BUFFER_DATA_SIZE;
1118 // free buffer chain starting from the second buffer
1119 int free_count = (b->flags & VLIB_BUFFER_NEXT_PRESENT) != 0;
1120 u32 chain_to_free = b->next_buffer;
1122 u32 len = vlib_buffer_length_in_chain (vm, b);
1123 u32 free_len = buf_len - b->current_data - b->current_length;
1124 int alloc_len = clib_max (len - free_len, 0); //use the free len in the first buffer
1125 int n_buffers = (alloc_len + buf_len - 1) / buf_len;
1126 u32 new_buffers[n_buffers];
1128 u32 n_alloc = vlib_buffer_alloc (vm, new_buffers, n_buffers);
1129 if (n_alloc != n_buffers)
1131 vlib_buffer_free_no_next (vm, new_buffers, n_alloc);
1135 vlib_buffer_t *s = b;
1136 while (s->flags & VLIB_BUFFER_NEXT_PRESENT)
1138 s = vlib_get_buffer (vm, s->next_buffer);
1139 int d_free_len = buf_len - b->current_data - b->current_length;
1140 ASSERT (d_free_len >= 0);
1141 // chain buf and split write
1142 u32 copy_len = clib_min (d_free_len, s->current_length);
1143 u8 *d = vlib_buffer_put_uninit (b, copy_len);
1144 clib_memcpy (d, vlib_buffer_get_current (s), copy_len);
1145 int rest = s->current_length - copy_len;
1149 ASSERT (vlib_buffer_get_tail (b) == b->data + buf_len);
1150 ASSERT (n_buffers > 0);
1151 b = vlib_buffer_chain_buffer (vm, b, new_buffers[--n_buffers]);
1152 //make full use of the new buffers
1153 b->current_data = 0;
1154 d = vlib_buffer_put_uninit (b, rest);
1155 clib_memcpy (d, vlib_buffer_get_current (s) + copy_len, rest);
1158 vlib_buffer_free (vm, &chain_to_free, free_count);
1159 b->flags &= ~VLIB_BUFFER_TOTAL_LENGTH_VALID;
1160 if (b == first) /* no buffers addeed */
1161 b->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
1162 ASSERT (len == vlib_buffer_length_in_chain (vm, first));
1163 ASSERT (n_buffers == 0);
1164 return buf_len - b->current_data - b->current_length;
1167 #endif /* included_vlib_buffer_funcs_h */
1170 * fd.io coding-style-patch-verification: ON
1173 * eval: (c-set-style "gnu")